[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <20200429053753.GA12533@lsv03152.swis.in-blr01.nxp.com>
Date: Wed, 29 Apr 2020 11:07:53 +0530
From: Calvin Johnson <calvin.johnson@....nxp.com>
To: Russell King - ARM Linux admin <linux@...linux.org.uk>,
"Rafael J. Wysocki" <rjw@...ysocki.net>,
Len Brown <lenb@...nel.org>
Cc: linux.cj@...il.com, Jeremy Linton <jeremy.linton@....com>,
Andrew Lunn <andrew@...n.ch>,
Andy Shevchenko <andy.shevchenko@...il.com>,
Florian Fainelli <f.fainelli@...il.com>,
Cristi Sovaiala <cristian.sovaiala@....com>,
Florin Laurentiu Chiculita <florinlaurentiu.chiculita@....com>,
Ioana Ciornei <ioana.ciornei@....com>,
Madalin Bucur <madalin.bucur@....nxp.com>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Heikki Krogerus <heikki.krogerus@...ux.intel.com>,
linux-arm-kernel@...ts.infradead.org, netdev@...r.kernel.org,
Diana Madalina Craciun <diana.craciun@....com>,
Laurentiu Tudor <laurentiu.tudor@....com>,
linux-acpi@...r.kernel.org, Marcin Wojtas <mw@...ihalf.com>,
Makarand Pawagi <makarand.pawagi@....com>,
"Rajesh V . Bikkina" <rajesh.bikkina@....com>,
Varun Sethi <V.Sethi@....com>, linux-kernel@...r.kernel.org,
Pankaj Bansal <pankaj.bansal@....com>,
"David S. Miller" <davem@...emloft.net>,
Heiner Kallweit <hkallweit1@...il.com>
Subject: Re: [net-next PATCH v2 0/3] Introduce new APIs to support phylink
and phy layers
On Mon, Apr 27, 2020 at 03:48:07PM +0100, Russell King - ARM Linux admin wrote:
> On Mon, Apr 27, 2020 at 08:02:38PM +0530, Calvin Johnson wrote:
> > On Mon, Apr 27, 2020 at 02:58:20PM +0100, Russell King - ARM Linux admin wrote:
> > > On Mon, Apr 27, 2020 at 06:54:06PM +0530, Calvin Johnson wrote:
> > > > Following functions are defined:
> > > > phylink_fwnode_phy_connect()
> > > > phylink_device_phy_connect()
> > > > fwnode_phy_find_device()
> > > > device_phy_find_device()
> > > > fwnode_get_phy_node()
> > > >
> > > > First two help in connecting phy to phylink instance.
> > > > Next two help in finding a phy on a mdiobus.
> > > > Last one helps in getting phy_node from a fwnode.
> > > >
> > > > Changes in v2:
> > > > move phy code from base/property.c to net/phy/phy_device.c
> > > > replace acpi & of code to get phy-handle with fwnode_find_reference
> > > > replace of_ and acpi_ code with generic fwnode to get phy-handle.
> > > >
> > > > Calvin Johnson (3):
> > > > device property: Introduce phy related fwnode functions
> > > > net: phy: alphabetically sort header includes
> > > > phylink: Introduce phylink_fwnode_phy_connect()
> > >
> > > Thanks for this, but there's more work that needs to be done here. I
> > > also think that we must have an ack from ACPI people before this can be
> > > accepted - you are in effect proposing a new way for representing PHYs
> > > in ACPI.
> >
> > Thanks for your review.
> >
> > Agree that we need an ack from ACPI people.
> > However, I don't think it is a completely new way as similar acpi approach to
> > get phy-handle is already in place.
> > Please see this:
> > https://elixir.bootlin.com/linux/v5.7-rc3/source/drivers/net/ethernet/apm/xgene/xgene_enet_hw.c#L832
>
> That was added by:
>
> commit 8089a96f601bdfe3e1b41d14bb703aafaf1b8f34
> Author: Iyappan Subramanian <isubramanian@....com>
> Date: Mon Jul 25 17:12:41 2016 -0700
>
> drivers: net: xgene: Add backward compatibility
>
> This patch adds xgene_enet_check_phy_hanlde() function that checks whether
> MDIO driver is probed successfully and sets pdata->mdio_driver to true.
> If MDIO driver is not probed, ethernet driver falls back to backward
> compatibility mode.
>
> Since enum xgene_enet_cmd is used by MDIO driver, removing this from
> ethernet driver.
>
> Signed-off-by: Iyappan Subramanian <isubramanian@....com>
> Tested-by: Fushen Chen <fchen@....com>
> Tested-by: Toan Le <toanle@....com>
> Signed-off-by: David S. Miller <davem@...emloft.net>
>
> The commit message says nothing about adding ACPI stuff, and searching
> the 'net for the posting of this patch seems to suggest that it wasn't
> obviously copied to any ACPI people:
>
> https://lists.openwall.net/netdev/2016/07/26/11
>
> Annoyingly, searching for:
>
> "drivers: net: xgene: Add backward compatibility" site:lore.kernel.org
>
> doesn't find it on lore, so can't get the full headers and therefore
> addresses.
>
> So, yes, there's another driver using it, but the ACPI folk probably
> never got a look-in on that instance. Even if they had been copied,
> the patch description is probably sufficiently poor that they wouldn't
> have read the patch.
>
> I'd say there's questions over whether ACPI people will find this an
> acceptable approach.
>
> Given that your patch moves this from one driver to a subsystem thing,
> it needs to be ratified by ACPI people, because it's effectively
> becoming a standardised way to represent a PHY in ACPI.
How can we get attention/response from ACPI people? I've now added ACPI
maintainers in the To list.
Thanks
Calvin
Powered by blists - more mailing lists